Interface Task<T>

Type Parameters:
T - The result type

public interface Task<T>
Represents an asynchronous task.
Note: The underlying task may already be started.
  • Method Details

    • isStarted

      boolean isStarted()
      Whether this task has started.
      Returns:
      True, if this task has already started.
    • onError

      @Nonnull Task<T> onError(@Nonnull Consumer<? super Throwable> callback)
      Provide a callback for exception handling.
      This is an asynchronous operation.

      The error will be logged regardless of your callback, this only exists to handle failures for other purposes.

      Parameters:
      callback - The error callback
      Returns:
      The current Task instance for chaining
      Throws:
      IllegalArgumentException - If null is provided
    • onSuccess

      @Nonnull Task<T> onSuccess(@Nonnull Consumer<? super T> callback)
      Provide a callback for success handling.
      This is an asynchronous operation.
      Parameters:
      callback - The success callback
      Returns:
      The current Task instance for chaining
      Throws:
      IllegalArgumentException - If null is provided
    • setTimeout

      @Nonnull Task<T> setTimeout(@Nonnull Duration timeout)
      Change the timeout duration for this task.
      This may be ignored for certain operations.

      The provided timeout is relative to the start time of the task. If the time has already passed, this will immediately cancel the task.

      Parameters:
      timeout - The new timeout duration
      Returns:
      The current Task instance for chaining
      Throws:
      IllegalArgumentException - If null is provided or the timeout is not positive
    • setTimeout

      @Nonnull default Task<T> setTimeout(long timeout, TimeUnit unit)
      Change the timeout duration for this task.
      This may be ignored for certain operations.

      The provided timeout is relative to the start time of the task. If the time has already passed, this will immediately cancel the task.

      Parameters:
      timeout - The new timeout duration
      unit - The time unit of the timeout
      Returns:
      The current Task instance for chaining
      Throws:
      IllegalArgumentException - If null is provided or the timeout is not positive
    • get

      @Nonnull T get()
      Blocks the current thread until the result is ready.
      This will not work on the default JDA event thread because it might depend on other events to be processed, which could lead to a deadlock.
      Returns:
      The result value
      Throws:
      UnsupportedOperationException - If this is called on the default JDA event thread
      CompletionException - If some exception occurred (such as TimeoutException).
      CancellationException - If the request was cancelled
    • cancel

      void cancel()
      Cancels the task and will emit a CancellationException.